Hold-down shoe for dado machines



March 9, 1954 B. E. THOMPSON 2,671,479

HOLD-DOWN SHOE FOR DADOE MACHINES Filed April 2, 1953 2 Sheets-Sheet l $.1 Thom avail INVENTOR ATTORNEYS.

March 1954 B. E. THOMPSON HOLD-DOWN SHOE FOR DADOE MACHINES 2 Sheets-Sheet 2 Filed April 2, 1953 B. E .TVZOTIZWSOR INVENTOR ATTORNEYS.

Patented Mar. 9, 1954 UNITED STATES AT'ENT OFFICE.

Brockman Earle Thompson, West Palm Beach, Fla.

eradication April 2... 3 Se ial No! 3 6,383

3: Glaims. 1

Thi in entio re s to a P e s sh or hold down device which particularly well adapted for cutting dadoes Qf uniform. depth with precision. Dado machines or tools are used for tting roov s. in. woce n nam or the. li e where it is necessary and. desirable that the grooves be of equal depth and properly located or positioned. My device is particularly adapted feruse with such mach n s earl. e es the perator to out su h roove wi p ion.- Th device takes the orm oi a. ve y s le att k-. ment which may h Quickly and; readily e to the huh of the. motor which drives he cuttin tool in such a manner as to provide a tool which will enable the operator to cut dadoes of uniform depth with great precision and which will maintain its adjusted position.

The main object of the invention is to provide a hold down shoe of the character described which will assure accurate work and which comprises only a few parts which are well adapted for production at comparatively low cost and which can be installed as an attachment on a machine now in use, if desired.

Further and more limited objects of the invention will appear as the description proceeds and by reference to the accompanying drawings in which like parts are designated by corresponding reference characters. In the accompanying drawings,

Fig. l is a view in end elevation of a dado machine having my improved attachment aflixed thereto.

Fig. 2 is a view similar to Fig. 1 but taken at right angles thereto.

Fig. 3 is a view in side elevation showing my improved attachment.

Referring now to the drawings the reference character M designates a motor which has projecting from side thereof a shaft designated by the reference character It. The reference character H designates a hub on the motor and in which the shaft In is journalled. Surrounding the hub portion I I and ailixed thereto are a plurality of yoke sections designated l3 and 14 which surround the hub section and are fixedly secured thereto by set screws i5. Disposed at either side of the yoke sections are a pair of exteriorly threaded rods designated by the reference characters I! and i8 and which are threadedly engaged with the arcuate yoke section or shoe i6. Also threadedly received over the exteriorly threaded rods I! and I8 are looking nuts I9 and 20 which have openings 2| and 22 therein to receive a tool or spanner wrench. The shoe I6 (Cl. LIL-136) 2. sit ate n hap a shown m learly Fig. l. and, xt n s vert a ly ownwa d y n a d rection t right an les t the f th sha t. Journ lle the lower ed of th sh e i5 roller 2?. wh ch adapted i ro a ei an a horizontal. si on is. paral l t oi the armed by he sea ii an :0- e ab e the ewith i cutt g tool. desi nated by he ferenc cha acte This ol m de up of. a sl raliiv ews or cuttin dev c Walsh disp sed sid by sid and i ab in is e: ion. re e nce hara t r it designate the teeth of e uttin to l. to s messiah a ly t the shaft by of t e .nut .15-

The reference character W designates the Work which is to be grooved. It should be unclerstood that this work is supported upon a base or platform which supports the work in a horizontal position and preferably has suitable guides thereon for guiding the work as it is moved past the cutting tool. It should be noted that the axis of rotation of the roller 22 and the axis of rotation of the shaft I0 and the cutting tool 23 are disposed parallel to each other. The roller is adapted to engage the end portion of the work as shown in Fig. 3 and to hold it in place and guide the work as it is passed through the machine. The depth of the groove is determined by the setting of the peripheral edge of the roller 22. This roller 22 and its associated parts provide a hold down shoe or guide for determining the thickness of the groove to be cut in a particular piece of work. It will be seen that the exteriorly threaded rods i7 and [8 may be adjusted to properly locate the position of the roller with respect to the cutting edge of the tool. The lock nuts [9 and 29 are then tightened to hold the shoe in its adjusted position.

It will now be clear that I have provided a hold down shoe and guide for dado machines which will accomplish the objects of the invention as herein'before stated. It is to be understood that various changes may be made in the details of construction and arrangements of parts without departing from the spirit of my invention. The invention is therefore limited only in accordance with the scope of the appended claims.

What is claimed is:

1. In combination with a power driven dado machine having a motor shaft projecting outwardly therefrom and on which the cutting tool is non-rotatably mounted and which has thereon a hub in which the motor shaft i journalled, a pair of arcuate yokes fitting over said hub and secured against relative movement with respect thereto, an arcuate shoe carried by said yokes and extending downwardly therefrom to a point adjacent the lower peripheral edge of said cutting tool, a roller journalled in the lower edge of said shoe for turning movement about a horizontal axis parallel to and spaced below the axis of rotation of said cutting tool and means for adjusting the vertical position of the lower peripheral edge of said roller while maintaining its axis of rotation horizontal and parallel with the axis of rotation of said cutting tool.

2. In combination with a power driven dado machine having a motor shaft projecting outwardly therefrom and on which the cutting tool is non-rotatably mounted and which has thereon a hub in which the motor shaft is journalled, a pair of arcuate yokes fitting over said hub and secured against relative movement with respect thereto, an arcuate shoe carried by said yokes and extending downwardly therefrom to a point adjacent the lower peripheral edge of said cuttin tool, a roller journalled in the lower edge of said shoe for turning movements about a horizontal axis parallel to and spaced below the axis of rotation of said cutting tool and means for adjusting the vertical position of the lower peripheral edge of said roller while maintaining its axis of rotation horizontal and parallel with the axis of rotation of said cutting tool, said means comprising a pair of oppositely disposed exteriorly threaded rods having their lower end fixed to said shoe and having their upper ends projecting through and threadedly engaged in openings provided in the opposite ends of said pair of yokes 4 and lock nuts for securing such rods in their adjusted position.

3. A guide device for use on a power operated dado machine which has a motor having a hub and a projecting shaft on which the dado cutting tool is non-rotatably secured comprising a yoke surrounding said hub and made up of an upper section and a lower section secured against relative movement, a shoe adjustably secured to said yoke for movement in a vertical plane, a roller journalled in the lower end of said shoe for rotation on a horizontal axis parallel with the axis of said shaft, means for adjusting the height 01' the lower peripheral edge of said roller relative to the cutting edge of said tool comprising a pair of exteriorly threaded rods having threaded engagement with both said yok sections and said shoe for raising and lowering said shoe and roller and means for locking said shoe in its adjusted position, the peripheral edge of said roller and the cutting edges of said tool lying in parallel but spaced apart horizontal planes when the roller is in an adjusted position.

BROCKMAN EARLE THOMPSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 733,744 Raettig July 14, 1903 1,576,671 Meyer Mar. 16, 1926 1,885,087 De Witt Oct. 25, 1932 2,140,120 Tomarin Dec. 13, 1938 2,189,246 Henry Feb. 6, 1940 

